1. Field of the Invention
The present invention relates to an eyeglass frame to hold eyeglass lenses, more specifically, to an eyeglass frame in which deformation or breaking of the eyeglass lenses is not generated even if temples of the eyeglass frame are opened widely.
2. Description of the Related Art
Generally, an eyeglass frame includes a front frame to hold right and left eyeglass lenses, and temples each being connected to a corresponding one of opposite ends of the front frame through a hinge. In such a front frame, there is a full rim type (for holding each lens by a rim extending around the entirety of the lens), and a rimless type called a half rim type or two points (for holding a part of each lens by a rim and another part of each lens by a screw, wire or string).
When a user typically uses the eyeglass frame, the temples are in a maximum open state or position relative to the front frame. On the other hand, when an eyeglass frame is fitted to the user, an open degree of each hinge connecting the front frame and the respective temple, or a bending degree of each of the temples is adjusted such that the temples do not impart a large force to a head of the user, and the temples are fitted to the head.
However, when the user mounts the eyeglasses on his or her head, or removes them from his or her head, the user tends to open the temples unconsciously and more widely than the maximum open state. Therefore, if the eyeglass frame is used for a long period, the temples become outwardly bent and gradually reach a state in which they do not fit the head, and hence it is difficult to use the eyeglasses. In addition, a large force is sometimes transmitted to the front frame due to an excessive opening of the temples. Consequently, breaking of the front frame, and further breaking of the eyeglass lenses are generated.
As shown in FIG. 6, there is disclosed a conventional eyeglass frame 110 in which, even if temples are opened widely, a force is not imparted to a front frame or eyeglass lenses (for reference, see JP2008-76743A). The eyeglass frame 110 has a generally L-character like shape and includes a pair of right and left lens stays 122 each holding an inner side portion of an eyeglass lens 160, a bridge 123 connecting the pair of lens stays 122, a connection arm 124 connected to each of the lens stays 122, and a temple 131 connected to each of the connection arms 124 through a hinge 130 to be rotatable inwardly and outwardly. Meanwhile, lens stoppers 162 to hold the eyeglass lenses 160 are provided on the lens stays 122.
Here, each of the eyeglass lenses 160 is attached to a corresponding one of the lens stays 122 at one point. Therefore, even if the temples 131 are opened widely, a force is not imparted to the eyeglass lenses 160. In addition, because the temples 131 and the connection arms 124 have elasticity, even if the temples are repeatedly opened widely, the opening operation or movement can be absorbed by the elasticity of the temples 131 and the connection arms 124, and has no effect on the lenses 160. Meanwhile, a nose pad 161 may be attached to each of the lens stays 122.
However, the structure of the conventional eyeglass frame cannot be applied to a full rim-type front frame made of a resin, because a design and a structure of eyeglasses are limited. Accordingly, it is desired that, even if a wide opening of the temples is repeated, a function having no effect on eyeglass lenses can be applied widely to eyeglasses having other design or structure.